Types of non-volatile memory such as flash memory may be organized according to blocks, which are typically erased prior to storing data in the blocks. Repeated erasures may eventually wear out types of non-volatile memory such as flash and may reduce an ability to retain data. An ability to retain data after repeated erasures is often referred to as “endurance”. Endurance may refer to a number of times a block of non-volatile memory may be erased and still operate reliably.
Endurance for various types of non-volatile memory such as NAND flash memory may be finite. As a result of having a finite endurance, data storage products that utilize types of non-volatile memory such as NAND flash memory may require a pass/fail test to repeatedly assess data retention capabilities of a given block. Repeated assessment of data retention capabilities may be needed if the given block has a propensity to go “bad” over a data storage operational life. An eventual failure of repeated pass/fail tests may result in removing the given block from a pool of available blocks.